Coronary artery disease is one of the leading causes of death worldwide. The ability to better diagnose, monitor, and treat coronary artery disease can be of life saving importance. Intravascular optical coherence tomography (OCT) is a catheter-based imaging modality that uses light to peer into coronary artery walls and generate images thereof for study. Utilizing coherent light, interferometry, and micro-optics, OCT can provide video-rate in-vivo tomography within a diseased vessel with micrometer level resolution.
Viewing subsurface structures with high resolution using fiber-optic probes makes OCT especially useful for minimally invasive imaging of internal tissues and organs. This level of detail made possible with OCT allows a clinician to diagnose, as well as monitor, the progression of coronary artery disease. OCT images provide high-resolution visualization of coronary artery morphology and can be used alone or in combination with other information such as angiography data and other sources of subject data to aid in diagnosis and treatment planning.
OCT imaging of portions of a patient's body provides a useful diagnostic tool for doctors and others. For example, imaging of coronary arteries by intravascular OCT may reveal the location of a narrowing or stenosis, which reduce blood flow and increase the risk of ischemia. This information helps cardiologists to choose between an invasive coronary bypass surgery and a less invasive catheter-based procedure such as angioplasty or stent delivery to mitigate the stenosis and restore blood flow. The presence of arterial side branches in the stenosis region also affects blood flow through the artery, and therefore is an important factor when designing a treatment plan for the patient.
The quantitative assessment of vascular pathology and its progression involves the calculation of different quantitative measures such as pressure drops which can rely on the accurate identification of fluid flow and geometry of the lumen, including side branch geometry. Side branches extending from a lumen in OCT images are often not easily identified. In part, this results because side branches can be obscured by the guidewire used in various OCT probes or otherwise obscured by stent struts, blood, and shadows.
Further, shadows and other imaging data artifacts can be challenging to resolve and eliminate. As a result, important landmarks along the length of an artery such as side branches can be mistaken for tissue or simply not identified. Given that placing a stent over a side branch can be damaging or when performed, it should be done knowingly, there is a need for a reliable technique that can identify side branches.
The present disclosure addresses these challenges and others.